Alternatively, you can uninstall Adobe Reader (33.5 MB), download and install Foxit PDF Reader(3.5MB) from HERE.
It's a much smaller file to download and uses a lot less resources than Adobe Reader.
Note: When installing FoxitReader, make sure to UN-check any pre-checked toolbar, or other garbage.
On this page:

6. Run Malwarebytes "Quick scan" once in a while to assure safety of your computer.

7. Run Temporary File Cleaner (TFC) weekly.

8. Download and install Secunia Personal Software Inspector (PSI): http://secunia.com/vulnerability_scanning/personal/. The Secunia PSI is a FREE security tool designed to detect vulnerable and out-dated programs and plug-ins which expose your PC to attacks. Run it weekly.

9. (optional) If you want to keep all your programs up to date, download and install FileHippo Update Checker.
The Update Checker will scan your computer for installed software, check the versions and then send this information to FileHippo.com to see if there are any newer releases.